Restore sessionStorage when chrome restarts.

content/browser/in_process_webkit/dom_storage_area.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/in_process_webkit/dom_storage_area.h"
 
 #include "base/logging.h"
 #include "content/browser/in_process_webkit/dom_storage_context.h"
 #include "content/browser/in_process_webkit/dom_storage_namespace.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebSecurityOrigin.h"
@@ skipping 56 matching lines @@
   CreateWebStorageAreaIfNecessary();
   bool somethingCleared;
   storage_area_->clear(WebURL(), somethingCleared);
   return somethingCleared;
 }
 
 void DOMStorageArea::PurgeMemory() {
   storage_area_.reset();
 }
 
+void DOMStorageArea::CopyDataTo(DOMStorageArea* other) {
+  for (unsigned i = 0; i < Length(); ++i) {
+    string16 key = Key(i).string();
+    WebStorageArea::Result result;
+    other->SetItem(key, GetItem(key).string(), &result);
+  }
+}
+
 void DOMStorageArea::CreateWebStorageAreaIfNecessary() {
   if (!storage_area_.get())
     storage_area_.reset(owner_->CreateWebStorageArea(origin_));
 }